The immunomodulatory drug thalidomide is the treatment of choice for erythema nodosum leprosum (ENL), an inflammatory cutaneous and systemic complication of multibacillary leprosy. To elucidate the mechanism of action of thalidomide in this syndrome, we prospectively investigated 20 patients with ENL who were treated with thalidomide for 21 days. All patients responded to treatment, with the majority of them having complete resolution of cutaneous lesions within 7 days. This response was associated with a marked but transient increase in ex vivo mitogen-induced expression of interleukin (IL)-2 and interferon- gamma by CD4(+) and CD8(+) T cells that was observed on treatment day 7, but these returned to pretreatment levels by day 21. Plasma tumor necrosis factor- alpha levels were not high at baseline, and they increased modestly during treatment. Plasma levels of IL-12 increased steadily during thalidomide treatment. Hence, the therapeutic effect of thalidomide in ENL appears to be associated with transient immune stimulation, which suggests that the drug may promote an active immunoregulatory response.

Quantification of gene expression is important to confirm changes in levels of gene expression in disease. Prior quantification methods include standard curves, absolute quantification, and relative quantification. This paper describes an analytic method for the relative quantification of Presenilin-1 (PS-1) in neurons and Forkhead-box (FOX) p3 in PBMNCs using real-time PCR analytic techniques. A comparative Ct method (deltadelatCt) is described in which the quantity of target normalized to a normalizer gene reference is given by 2-deltadelatCt where deltadelatCt = [Ct of the gene of interest in the unknown specimen - Ct normalizer gene in the unknown specimen] - [Ct of the gene of interest in the calibrator specimen - Ct normalizer gene in the calibrator specimen]. The calibrator specimen is ideally from a non-treated control specimen and is analyzed on every assay plate with the unknown specimens of interest. The use of the deltadelatCt methodology allows for a higher throughput and a more economical approach to investigate gene expression. We applied this methodology to the quantification of PS-1 and FOXp3 genes and compare the levels of expression by normalizing to different normalizer genes using the deltadelatCt methodology. We find that use of GAPDH is the optimum normalizer gene for the genes analyzed in neurons from human brain and in PBMNCs.